Well, I personally would invest in a way to getting more time cubes, that way you're able to get more easily, and buy the expensive stuff.Afterwards, I'd suggest DPS, raising the DPS of your team will make it easier to pass levels, and besides, they're relatively cheap, from what I have gathered.After all those maybe the ones relative to gold multipliers and cubes, that will also help you out with passing the waves faster, since more gold, more upgrades, and so on.These are my 3 top recommendations, I do not know if I helped you out, but I hope I did, and may you have a good day. From my experience, spend your time cubes on abilities that increase damage for the most part, pretty much everything else is useless until you get into the much higher waves.
Time Clickers for PC cheats - Cheating Dome has all the latest cheat codes, unlocks, hints and game secrets you need. Destroy cubes to collect gold. Spend gold to upgrade your weapons. Time Cubes appear at wave 100. Spend Time Cubes on Artifacts. Weapon Cubes.
Basically focus on team DPS damage, since this is what i do and any change left over i spend on other random damage artifacts. Starting Gold is also something worth purchasing from time to time.Also, use Windows Mouse Keys function. By holding down 2 buttons on your numeric keypad you fire at a rate of 100clicks/persec. Way higher than the artifacts can max out at in auto aim mode. For example, i was at wave 1400 and thought i should try and make it to the next wave of 1550 for the next achievement.
And i'm still in the the same Timeline now and i'm about to hit wave 2000.I have only earned a total of 95,000 Time Cubes and around 6,000 Weapon cubes in my entire career and Timewarped just 36 times, so really i'm quite weak atm. But yet i can make it to wave 2000 and maybe even 2150 if i'm lucky. Sure you have to hold down the 2 buttons, but i simply play like that for around 30mins to an hour, and come back 9 to 10 hours later.
By which time i've earned quite a bit of gold to boost my abilities and rinse and repeat.It's actually quite surprising how far you can get just by using Mouse Keys, even if your very weak. Also by going further you earn far more time cubes/weapon cubes than wasting your time restarting timelines often. And you'll earn the majority of achievements in the process.